Remote browsing session management

ABSTRACT

A browsing process is directed to the generation and management of a browse session at a network computing provider. A client computing device requests a remote browse session instance at a network computing provider. The browse session instance may correspond to requested network content. The network computing provider determines a browse configuration. The browse configuration may identify a communication protocol and various processing actions. The network computing provider retrieves the requested content through an instantiated network browse session instance, and performs a first set of processing actions to generate a processing result. The network computing provider determines whether the requested content is likely to perform high risk operations on the client computing device, and notifies the user or transmits a processed representation of the requested content to the user such that the likelihood of high risk operations being performed on the client computing device is reduced.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No. 13/316,309, entitled REMOTE BROWSING SESSION MANAGEMENT, and filed Dec. 9, 2011, now U.S. Pat. No. 9,009,334, the entirety of which is incorporated by reference herein.

BACKGROUND

Generally described, computing devices and communication networks can be utilized to exchange information. In a common application, a computing device can request content from another computing device via the communication network. For example, a user at a personal computing device can utilize a software browser application, typically referred to as a browser software application, to request a Web page from a server computing device via the Internet. In such embodiments, the user computing device can be referred to as a client computing device and the server computing device can be referred to as a content provider.

With reference to an illustrative example, a requested Web page, or original content, may be associated with a number of additional resources, such as images or videos, that are to be displayed with the Web page. In one specific embodiment, the additional resources of the Web page are identified by a number of embedded resource identifiers, such as uniform resource locators (“URLs”). In turn, software on the client computing devices, such as a browser software application, typically processes embedded resource identifiers to generate requests for the content. Accordingly, in order to satisfy a content request, one or more content providers will generally provide client computing devices data associated with the Web page as well as the data associated with the embedded resources.

Once the client computing device obtains the Web page and associated additional resources, the content may be processed in a number of stages by the software browser application or other client computing device interface. For example, and with reference to the above illustration, the software browser application may parse the Web page to process various HTML layout information and references to associated resources, may identify and process Cascading Style Sheets (“CSS”) information, may process and instantiate various Javascript code associated with the Web page, may construct a native object model to represent one or more components of the Web page, and may calculate various layout and display properties of the processed content for presentation to a user.

From the perspective of a user utilizing a client computing device, a user experience can be defined in terms of the performance and latencies associated with obtaining network content over a communication network, such as obtaining a Web page, processing embedded resource identifiers, generating requests to obtain embedded resources, and rendering content on the client computing device. Latencies and performance limitations of any of the above processes may diminish the user experience. Additionally, latencies and inefficiencies may be especially apparent on computing devices with limited resources, such as processing power, memory or network connectivity such as netbooks, tablets, smartphones, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a block diagram illustrative of a content delivery environment including a number of client computing devices, content provider, a content delivery network service provider, and a network computing provider;

FIG. 2 is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of a new browse session request from a client computing device to a network computing provider;

FIG. 3 is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of a request for a network resource from a network computing provider to a content provider;

FIG. 4A is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of one or more requests corresponding to one or more embedded resources from a network computing provider to a content provider and content delivery network;

FIG. 4B is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing, in different processing modes, of one or more requests corresponding to one or more embedded resources from a network computing provider to a content provider and content delivery network;

FIG. 5A is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of browse session data and user interaction data between a network computing provider and client computing device;

FIG. 5B is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of network resources, browse session data and user interaction data between a network computing provider and client computing device when in remote browsing mode;

FIG. 6A is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of an additional new browse session request from a client computing device to a network computing provider;

FIG. 6B is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of an additional new browse session in response to a request from a client computing device to a network computing provider;

FIG. 6C is a block diagram of the content delivery environment of FIG. 1 illustrating the management and termination of a browse session request;

FIG. 7A is a user interface diagram depicting an illustrative browser interface and display of browse session content;

FIG. 7B is a user interface diagram depicting an illustrative browser interface and display of a high risk content warning;

FIG. 8 is a diagram depicting illustrative browser content processing actions as a series of processing subsystems;

FIG. 9 is a flow diagram illustrative of a new browse session routine implemented by network computing provider;

FIG. 10 is a flow diagram illustrative of a client new browse session interaction routine implemented by a client computing device; and

FIG. 11 is a flow diagram illustrative of a process user interaction routine implemented by a client computing device;

FIG. 12 is a flow diagram illustrative of a routine for processing browsing requests in remote browsing mode, as implemented by network computing provider;

FIG. 13 is a flow diagram illustrative of a routine for processing browsing requests for blacklisted network resources, as implemented by a network computing provider; and

FIG. 14 is a flow diagram illustrative of a routine for monitoring browsing activity to determine high risk operations, as implemented by network computing provider.

DETAILED DESCRIPTION

Generally described, the present disclosure is directed to the generation and management of a remote application session between client computing devices and content providers in conjunction with a network computing provider. Specifically, aspects of the disclosure will be described with regard to the processing of requests for a browse session by a client computing device with a content provider. A network computing provider can receive network resource requests from the client computing device, and can retrieve and perform processing on the requested network resources before returning them to the client computing device. The network computing provider can determine whether the network resources requested by the client computing device may be known to elicit malicious or otherwise high risk operations on the client computing device. If so, the network computing provider can take certain actions to protect the client computing device from receiving, executing or otherwise processing the identified content. The protective actions can include establishment of a remote desktop connection and transmission of warnings to the user of the client computing device.

Although aspects of the embodiments described in the disclosure will focus, for the purpose of illustration, on the management of a remote browse session, one skilled in the art will appreciate that the techniques disclosed herein may be applied to any number of software processes or applications. Further, although various aspects of the disclosure will be described with regard to illustrative examples and embodiments, one skilled in the art will appreciate that the disclosed embodiments and examples should not be construed as limiting.

With reference to an illustrative example, a user may cause a client computing device to load a software browser application (henceforth referred to as a “browser”) for accessing content provided by one or more content providers. Illustratively, the accessed content may include a collection of one or more network resources (e.g., a Web page) and embedded resources such as images, video, audio, text, executable code, and other resources. In one embodiment, the browser may have a content display area or pane for displaying the accessed network content in addition to one or more local interface components, such as toolbars, menus, buttons, or other user interface controls. Local interface components may be managed and controlled by the software browser application or any other process executing or implemented locally at the client computing device. Illustratively, managing user interface controls locally may allow for a responsive user interface, as interactions by the user are processed locally on the client computing device.

Subsequent to the browser being loaded, a user or automated browser process may cause the client computing device to transmit a request to access content from a content provider by establishing a browse session with a network computing provider across a private or public network. The browse session request may include information identifying one or more sources for the requested content. The identifiers can be in the form of network addresses of network resources, such as a Web site or other network accessible piece of content. For example, the user may select or enter a URL, (e.g., http://www.xyzwebsite.com) into a browser window, causing the client computing device to transmit a request for a new browse session to the network computing provider, including the selected URL. The address or location of a network computing provider capable to service the browse session request may be hardcoded into the browser, may be configurable by the user, may be obtained from a network address service, or may be determined in any other way.

In an illustrative embodiment, responsive to the browse session request received from the client computing device, the network computing provider may instantiate or cause to have instantiated one or more computing components associated with the network computing provider that will host a browser software application. For example, the network computing provider can instantiate, or cause to have instantiated, an instance of a virtual machine that includes a software browser application capable of requesting resources from a communication network. Illustratively, in some situations, one or more devices associated with the network computing provider may be located in a data center or other robustly networked computing environment, and, as compared to the client computing device, may experience relatively little latency or delay when obtaining network resources.

Using the instantiated network computing components, the network computing provider may request the identified network resource(s) from one or more content providers, a content delivery network, or a local or associated cache component. For example, the browser software application on the instantiated network computing component can process a primary network resource and then generate additional content requests for content identified in one or more embedded resource identifiers (e.g. pictures, video files, etc.). Illustratively, in the case of other, non-browser, applications, network resources, or content may include any file type or format known in the art and supported by the specific software application.

Having obtained the requested content (e.g., the requested network resource and embedded resources), the network computing provider may determine whether the requested content should be transmitted to the client computing device. For example, the network computing provider can process the requested content and observe whether it performs malicious or other operations determined to be of an unacceptable risk level. In another example, the network computing provider can determine whether the processing of the requested content results is in contradiction to a defined set of best practices, such as total processing time, computing device resources utilized, and the like. Thereafter, the network computing provider can transmit warnings to the client computing device before transmitting the content.

The network computing provider may also identify a remote session browsing configuration specifying a remote session communication protocol for use in transmitting the requested content, user interaction data, intermediate processing results, and other information between the browser being executed on the client computing device and the browser being executed at the instantiated network computing component on the computing and storage provider. The information exchanged between the browser on the instantiated network computing component and the browser on the client computing device can be generally referred to as “browser session information.”

In addition to specifying a remote session communication protocol for transmitting information between the client computing device and the instantiated network computing component, in one embodiment, the identified remote session browsing configuration may specify that one or more processing actions to be performed on the requested content are to be performed at the network computing provider rather than, or in addition to, at the client computing device The determination of which actions are to be performed on the network computing provider can be based, at least in part, on the probability that the requested content may perform malicious or otherwise high risk operations. For purposes of illustration, the processing of network content by a browser may involve various processing actions before content can be rendered in an appropriate form on a client computing device. A Web page, for example, may be parsed and processed to process various HTML layout information and references to associated resources or embedded content such as CSS style sheets and Javascript, as well as embedded content objects such as images, video, audio, etc. Each object or piece of code may be parsed and processed before a representative object model corresponding to the web page may be constructed and processed further for layout and display. In accordance with the selected remote session browsing configuration, the client computing device and the instantiated network computing component may exchange processing results via browser session information (e.g., state data or display data representing the requested content). When the user of the client computing device wishes to enter a purely remote browsing mode, all of the processing can occur at the network computing provider, and a remote desktop connection may be established.

FIG. 1 is a block diagram illustrative of a networked computing environment 100 for the management and processing of content requests. As illustrated in FIG. 1, the networked computing environment 100 includes a number of client computing devices 102 (generally referred to as clients) for requesting content and content processing from a content provider 104, CDN service provider 106, or network computing provider 107. In an illustrative embodiment, the client computing devices 102 can corresponds to a wide variety of computing devices including personal computing devices, laptop computing devices, hand-held computing devices, terminal computing devices, mobile devices (e.g., mobile phones, tablet computing devices, etc.), wireless devices, various electronic devices and appliances and the like. In an illustrative embodiment, the client computing devices 102 include necessary hardware and software components for establishing communications over a communication network 108, such as a wide area network or local area network. For example, the client computing devices 102 may be equipped with networking equipment and browser software applications that facilitate communications via the Internet or an intranet. The client computing devices 102 may have varied local computing resources such as central processing units and architectures, memory, mass storage, graphics processing units, communication network availability and bandwidth, etc.

The networked computing environment 100 can also include a content provider 104 in communication with the one or more client computing devices 102 or other service providers (e.g., CDN service provider 106, network computing provider 107, etc.) via the communication network 108. The content provider 104 illustrated in FIG. 1 corresponds to a logical association of one or more computing devices associated with a content provider. Specifically, the content provider 104 can include a web server component 110 corresponding to one or more server computing devices for obtaining and processing requests for content (such as Web pages) from the client computing devices 102 or other service providers. The content provider 104 can further include an origin server component 112 and associated storage component 114 corresponding to one or more computing devices for obtaining and processing requests for network resources from the CDN service provider. The content provider 104 can still further include an application server computing device 111, such as a data streaming server, for processing streaming content requests. One skilled in the relevant art will appreciate that the content provider 104 can be associated with various additional computing resources, such as additional computing devices for administration of content and resources, DNS name servers, and the like. For example, although not illustrated in FIG. 1, the content provider 104 can be associated with one or more DNS name server components that would be authoritative to resolve client computing device DNS queries corresponding to a domain of the content provider.

With continued reference to FIG. 1, the networked computing environment 100 can further include a CDN service provider 106 in communication with the one or more client computing devices 102 and other service providers via the communication network 108. The CDN service provider 106 illustrated in FIG. 1 corresponds to a logical association of one or more computing devices associated with a CDN service provider. Specifically, the CDN service provider 106 can include a number of Point of Presence (“POP”) locations 116, 122, 128 that correspond to nodes on the communication network 108. Each CDN POP 116, 122, 128 includes a DNS component 118, 124, 130 made up of a number of DNS server computing devices for resolving DNS queries from the client computers 102. Each CDN POP 116, 122, 128 also includes a resource cache component 120, 126, 132 made up of a number of cache server computing devices for storing resources from content providers and transmitting various requested resources to various client computers. The DNS components 118, 124, and 130 and the resource cache components 120, 126, 132 may further include additional software and/or hardware components that facilitate communications including, but not limited to, load balancing or load sharing software/hardware components.

In an illustrative embodiment, the DNS component 118, 124, 130 and resource cache component 120, 126, 132 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the CDN POPs 116, 122, 128 are illustrated in FIG. 1 as logically associated with the CDN service provider 106, the CDN POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, one skilled in the relevant art will appreciate that the CDN service provider 106 can be associated with various additional computing resources, such as additional computing devices for administration of content and resources, and the like.

With further continued reference to FIG. 1, the networked computing environment 100 can also include a network computing provider 107 in communication with the one or more client computing devices 102, the CDN service provider 106, and the content provider 104 via the communication network 108. The network computing provider 107 illustrated in FIG. 1 also corresponds to a logical association of one or more computing devices associated with a network computing provider. Specifically, the network computing provider 107 can include a number of Point of Presence (“POP”) locations 134, 142, 148 that correspond to nodes on the communication network 108. Each POP 134, 142, 148 includes a network computing component (NCC) 136, 144, 150 for hosting applications, such as data streaming applications, via a number of instances of a virtual machine, generally referred to as an instance of an NCC. One skilled in the relevant art will appreciate that NCC 136, 144, 150 could include physical computing device resources and software to provide the multiple instances of a virtual machine or to dynamically cause the creation of instances of a virtual machine. Such creation can be based on a specific request, such as from a client computing device, or the NCC can initiate dynamic creation of an instance of a virtual machine on its own. Each NCC POP 134, 142, 148 also includes a storage component 140, 146, 152 made up of a number of storage devices for storing any type of data used in the delivery and processing of network or computing resources, including but not limited to user data, state information, processing requirements, historical usage data, and resources from content providers that will be processed by an instance of an NCC 136, 144, 150 and transmitted to various client computers, etc. The NCCs 136, 144, 150 and the storage components 140, 146, 152 may further include additional software and/or hardware components that facilitate communications including, but not limited to, load balancing or load sharing software/hardware components for selecting instances of a virtual machine supporting a requested application and/or providing information to a DNS nameserver to facilitate request routing.

In an illustrative embodiment, NCCs 136, 144, 150 and the storage components 140, 146, 152 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. For example, a network computing provider 107 may maintain separate POPs for providing the NCC and the storage components. Additionally, although the NCC POPs 134, 142, 148 are illustrated in FIG. 1 as logically associated with a network computing provider 107, the NCC POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, one skilled in the relevant art will appreciate that the network computing provider 107 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, and the like. Even further, one skilled in the relevant art will appreciate that the components of the network computing provider 107 and components of the CDN service provider 106 can be managed by the same or different entities.

With reference now to FIGS. 2-6, the interaction between various components of the networked computing environment 100 of FIG. 1 will be illustrated. Specifically, FIGS. 2-6 illustrate the interaction between various components of the networked computing environment 100 for the exchange of content between a client computing device 102 and a content provider 104 via the network computing provider 107. For purposes of the example, however, the illustration has been simplified such that many of the components utilized to facilitate communications are not shown. One skilled in the relevant art will appreciate that such components can be utilized and that additional interactions would accordingly occur without departing from the spirit and scope of the present disclosure.

With reference to FIG. 2, the process can begin with the generation and processing of a browse session request from a client computing device 102 to a network computing provider 107 will be described. Illustratively, the client computing device 102 may load a browser for viewing network content in response to an event or user request. Subsequent to the browser being loaded, the browser may be implemented to request a new browse session. From the perspective of the user of the client computing device, the request for the new browse session corresponds to the intended request to transmit the request to one or more corresponding content providers 104. Illustratively, this request may be generated automatically as a result of the browser loading (e.g., a request for a default or “home” page), or may be generated as a result of a user following a link or entering a network address into an address bar. As illustrated in FIG. 2, the browse session request is transmitted first to a network computing provider 107. In an illustrative embodiment, the network computing provider 107 utilizes a registration application program interface (“API”) to accept browse session requests from the client computing device 102. The browse session request can include network address information corresponding to a requested network resource, which may be in any form, including, but not limited to, an Internet Protocol (“IP”) address, a URL, a Media Access Control (“MAC”) address, etc.

Subsequent to the receipt of the browse session request, the network computing provider 107 may select an associated network computing component (hereinafter “NCC”) point of presence (hereinafter “POP”) such as NCC POP 142 to service the browse session request. The selection of the NCC POP may determine the processing and network resources available to the instantiated virtual machine. The selection of processing and network resources and the provisioning of software at the NCC POP instance may be done, at least in part, in order to optimize communication with content providers 104 and client computing devices 102.

With reference to FIG. 3, an illustrative interaction for generation and processing of a request for a network resource from a network computing provider 107 to a content provider 104 will be described. As illustrated in FIG. 3, the selected NCC POP 142 may generate a browse session corresponding to one or more content providers based on a browse session request, such as the illustrative browse session request depicted in FIG. 2 above. Illustratively, instantiating a new browse session instance may include loading a new virtual machine instance and/or browser instance at the NCC POP 142, reserving or allocating device memory, storage or cache space, processor time, network bandwidth, or other computational or network resources for the new browse session.

Subsequent to initializing a new browse session instance, NCC POP 142 may provide a request for a network resource to a content provider 104 based on a network address included in the browse session request. For example, a browse session request may include a URL for a Web page, such as “http://www.xyzsite.com/default.htm.” NCC POP 142 may resolve the URL to an IP address through a DNS resolver associated with the network computing provider (not shown), and may request the Web page from the content provider 104 at the resolved IP address. In various embodiments, a network resource may be retrieved from any combination of content providers, content delivery network (hereinafter “CDN”) servers, or caches associated with the network computing provider 107. For example, the network computing provider may check if a resource is stored in a local cache or in another server or service provider associated with the network computing provider 107. If a network resource is stored in a local or associated location, the NCC POP 142 may retrieve the network resource from the local or associated location rather than from the third party content provider 104 or CDN service provider 106. Illustratively, the NCC POP 142 may provide requests for any number of network resources as included in the browse session request, and may obtain these network resources from any number of different sources, sequentially or in parallel.

As illustrated in FIG. 3, the content provider 104 receives the resource request from the NCC POP 142 and processes the request accordingly. In one embodiment, the content provider 104 processes the resource request as if it were originally provided by the client computing device 102. For example, the content provider 104 may select the type of content, ordering of content, or version of content according to the requirements of the requesting client computing device 102. In another embodiment, the content provider 104 may be provided with information that provides information associated with the NCC POP 142 for utilization in providing the requested content (e.g., an available amount of processing resources or network bandwidth).

Subsequent to obtaining the requested network resource from the content provider 104 (or other source designated by the content provider), the NCC POP 142 may process the network resource to extract embedded resource identifiers and gather information for determination of a remote session browsing configuration. For example, a network resource such as a Web page may include embedded CSS style information and Javascript as well as embedded resource identifiers to additional resources such as text, images, video, audio, animation, executable code, and other HTML, CSS, and Javascript files. In the process of extracting the embedded resource identifiers, the NCC POP 142 may gather information about the processed network resources for later use in the determination of a remote session browsing configuration as discussed below with reference to FIG. 4A.

With reference to FIG. 4A, an illustrative interaction for generation and processing of one or more requests corresponding to one or more embedded resources from a network computing provider to a content provider and content delivery network is disclosed. As illustrated in FIG. 4A, the selected NCC POP 142 may provide resource requests to one or more sources of content such as content provider 104 and CDN POP 116. The resource requests may correspond to embedded resources based on one or more embedded resource identifiers extracted from a requested network resource (e.g., a Web page) as described in FIG. 3 above. In various embodiments, embedded resources may be retrieved from any combination of content providers, CDN servers, or caches associated with the network computing provider 107. For example, the network computing provider may check if an embedded resource is stored in a local cache or in another server or service provider associated with the network computing provider 107. If an embedded resource is stored in a local or associated location, the NCC POP 142 may retrieve the embedded resource from the local or associated location rather than the third party content provider or CDN. Illustratively, the NCC POP 142 may provide requests for any number of embedded resources referenced by a network resource, and may obtain these embedded resources from any number of different sources, sequentially or in parallel. Subsequent to obtaining the requested resources, the NCC POP 142 may process the resources and requested content to determine a remote session browsing configuration for the processing and communication of content to the client computing device 102.

With reference to FIG. 4B, an illustrative interaction for generation and processing of one or more requests corresponding to one or more embedded resources from a network computing provider to a content provider 104 and content delivery network 106 is disclosed. In contrast to the illustrative interaction of FIG. 4A, describe above, the interaction illustrated in FIG. 4B occurs when a requested resource has corresponds to an identification of known resource identifiers, often referred to as a blacklist. For example, the NCC POP 142 may maintain a list of resources (by their identifiers) which are associated with an increased probability of high risk operations, including viruses, Trojan horses, unexpected system file access, etc., as described below with respect to FIGS. 12-14. In the interaction illustrated in FIG. 4B, a request processed in an existing browse session instance can reference any number of embedded resources. If one of the embedded resources is blacklisted, a new browse session instance can be created to process the blacklisted resource, so that any high risk operation does not affect the exiting browse session instance.

With reference to FIG. 5A, an illustrative interaction for generation and processing of processing results and user interaction data between a network computing provider and client computing device is disclosed. As previously described, in one embodiment, the respective browsers on the instantiated network computing component and the client computing device 102 can exchange browsers' session information related to the allocation and processing of the requested resources at the instantiated network computing component and client computing device. As illustrated in FIG. 5A, the selected NCC POP 142 may provide an initial processing result to the client computing device 102 over the network 108. The initial processing result may correspond to requested network content, such as a Web page, along with associated embedded resources processed by the NCC POP 142 in accordance with a selected remote session browsing configuration as described in FIG. 4A above. The NCC POP 142 also makes a determination of which additional processes will be conducted at the NCC POP 142, at the client computing device 102, or both. Subsequent to receiving an initial processing result and the allocation of processes, the client computing device 102 may perform any remaining processing actions on the initial processing result as required by the selected remote session browsing configuration, and may display the fully processed content in a content display area of a browser. The client computing device 102 may process any local user interactions with local interface components or content elements locally, and may provide user interactions requiring remote processing to the network computing provider 107. The network computing provider 107 may provide updated processing results to the client computing device in response to changes to the content or remote user interaction data from the client computing device.

With reference to FIG. 5B, an illustrative interaction for generation and processing of processing results and user interaction data between a network computing provider and client computing device is disclosed. As previously described, in one embodiment, the respective browsers on the instantiated network computing component and the client computing device 102 can exchange browser session information related to the allocation and processing of the requested resources at the NCC POP 142 and client computing device 102. When the resource has a heightened probability of performing high risk operations, either the end user of client computing device 102, or the NCC POP 142, can choose to continue processing the resource in a remote browsing mode. In such a case, the processing of the resource on the client computing device 102 can be cancelled, and the resource can be discarded from the client computing device 102. Rendering and execution of the resource in the instance of the browsing application of the NCC POP 142 can continue, and a remote desktop connection can be established so that the end user of the client computing device 102 can continue to interact with the resource even though it is executing solely on the NCC POP 142.

With reference to FIG. 6A, a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of an additional new browse session request from a client computing device to a network computing provider is disclosed. As illustrated in FIG. 6A, a second new browse session request may be sent to network computing provider 107 from client computing device 102 across network 108. In an illustrative embodiment, the network computing provider 107 utilizes a registration API to accept browse session requests from the client computing device 102.

The additional browse session request may be generated by a client computing device 102 in response to a user opening up a new browser window with a new content display area, opening a new content display area in an existing browser window (e.g., opening a new tab in a browser), requesting new network content in an existing content display area (e.g., following a link to a new network resource, or entering anew network address into the browser), or any other user interaction. For example, a user browsing a first Web page corresponding to a first browse session instance may follow a link that opens a new tab or browser window to view a second Web page. In one embodiment, any required steps of obtaining and processing content associated with the second Web page may be performed by the currently instantiated network computing component in which the browser can handle the processing of both resource requests. In another embodiment, the client computing device 102 request may be processed as a new browse session request to the network computing provider 107, including the network address of the second Web page. In this embodiment, the browser on the client computing device may not specifically request a separate browse session, and a user's interaction with the browser on the client computing device 102 may appear to be part of a same browsing session. As described above with regard to FIGS. 2 and 3, the network computing provider 107 may cause an instantiation of a network computing component for obtaining and processing content associated with the second web page. In other embodiments, a new browse session request may be generated by the client computing device 102 corresponding to sections of a network resource (e.g., frames of a Web page), individual network resources, or embedded resources themselves, data objects included in a set of content, or individual network resources.

Illustratively, the additional browse session request may include any number of pieces of data or information including, but not limited to, information associated with a user, information associated with the client computing device 102 (e.g., hardware or software information, a device physical or logical location, etc.), information associated with the network 108, user or browser preferences (e.g., a requested remote session browse protocol, a preference list, a decision tree, or other information), information associated with the network computing provider 107, information associated with one or more pieces of requested network content (e.g., the network address of a network resource), etc. Requested content may include any manner of digital content, including Web pages or other documents, text, images, video, audio, executable scripts or code, or any other type of digital resource.

Subsequent to the receipt of the browse session request, the network computing provider 107 may select an associated network computing component such as NCC POP 142 to service the browse session request. As discussed above with reference to FIG. 2, a network computing provider 107 may select an NCC POP to service a browse session request based on any number of factors, including, but not limited to available NCC POP resources (e.g., available memory, processor load, network load, etc.), a financial cost of servicing the browse session request at the NCC POP, the NCC POP location respective to a client computing device 102, content provider 112, or CDN POP 116, a NCC POP cache status (e.g., whether a requested resource is already stored in an NCC POP cache), etc. In one embodiment, the network computing provider 107 may select a number of NCC POPs to service a browse session request. Illustratively, although the network computing provider 107 is depicted here for purposes of illustration as selecting NCC POP 142, the network computing provider 107 may select any extant NCC POP to service the browse session request. For example, a single client computing device 102 may simultaneously or sequentially provide three different browse session requests to the network computing provider 107 corresponding to different network resources. The network computing provider 107 may select different NCC POPs for each browse session request, the same NCC POP for all three browse session requests, or any combination thereof. As discussed above, the decision whether to select a different NCC POP than was utilized for a previous or simultaneous browse session request may be made on the basis of available system resources, randomly, or according to any other factor as discussed above and with regards to FIG. 2.

With reference to FIG. 6B, a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of an additional request from client computing device to a network computing provider is disclosed. As illustrated in FIG. 6B, a second resource request may be sent to network computing provider 107 from client computing device 102 across network 108. The new request can correspond to a blacklisted resource as described above with respect to FIG. 5B. In such a case, the NCC POP 142 can initialize a new browse session instance to process the blacklisted resource in a secure mode, while maintaining the previously requested resource in the previously initialized browse session instance so that it is available if the user wishes to return to it, for example by pressing the back button on the browser application. Alternatively, the NCC POP 142 can be configured to initialize a new browse session instance for each request made by the client computing device 102 in order to maximize the compartmentalization of the requested resources.

With reference to FIG. 6C, a block diagram of the content delivery environment of FIG. 1 illustrating the management and termination of a browse session instance is disclosed. As illustrated in FIG. 6C, an administrative process can execute on the NCC POP 142 or another component of the network computing provider 107. The administrative process can observe the operation of each browse session instance, and when it determines that a browse session instance is processing a resource that is executing malicious code or otherwise performing high risk operations, the administrative process can terminate the browse session instance, and instantiate a new browse session instance in its place. In some embodiments, the new browse session instance can then load the problematic resource. However, the new browse session instance can be provided with information about how and why the terminated browse session instance processed the resource, and can therefore be in a better state to deal with potential high risk operations. In some embodiments, the new browse session instance can default into a heightened security mode, such as remote browsing mode.

FIG. 7A is a user interface diagram depicting an illustrative browser interface and display of browse session content. As described above with reference to FIG. 5A, a browser 700 may have a content display area 702, as well as one or more one or more local interface components. These local interface components may include toolbars, menus, buttons, address bars, scroll bars, window resize controls, or any other user interface controls. For example, the local interface components may include a remote mode button 704 and a title bar 708. A notification window 708 may also be displayed by the browser interface. The notification window 708 can include an image 710. Illustratively, local interface components may be displayed as separate from the content display area or may be overlaid or embedded in the content display area.

Interactions with local interface components may be treated as local user interactions or remote user interactions depending on the processing required by the interaction and the remote session browsing configuration. For example, the selection of a preferences option in a browser menu may be handled entirely as a local user interaction by a browser. The processing required to display the menu, provide visual feedback regarding the selection, display the preferences window, and process the changes made to the browser preferences may be performed locally. As discussed above, processing user interactions locally may provide greater responsiveness at the browser as opposed to sending user interaction data to the NCC POP 142 for processing. As another example, when using a remote session browsing configuration that specifies extensive processing on the NCC POP 142 (e.g., a remote session browsing configuration using a remote session communication protocol such as RDP), the selection of a content refresh button in a browser toolbar may be handled both as a local user interaction and a remote user interaction. The limited processing required to provide interface feedback corresponding to the button selection may be handled at the client computing device 102 in order to provide the appearance of interface responsiveness, while the refresh command, which may require processing of the network content displayed in the content display area of the browser, may be sent as user interaction data to the NCC POP 142 for processing. The NCC POP 142 may then transmit updated processing results corresponding to the refreshed network content back to the client computing device 102 for display.

When a browse session enters remote browsing mode, by activating remote mode button 704 or as otherwise described herein, notifications may be displayed to the user. For example, the title bar 706 or another area of the browser 700 may change texture, color, or otherwise indicate the changed state of the browser. In some embodiments, the title bar 706 can display a textual indication of the current browsing mode, as illustrated in FIG. 7A.

When a malicious or otherwise potentially high risk web site has been requested or displayed, a notification can be displayed to the user. As illustrated in FIG. 7B, the notification can include a flash of color or a change in the texture of an area 712 of the browser 700. A textual warning can be displayed in the address bar 714, the title bar 706, or some other visible portion of the browser 700. Notifications displayed to the user can also include a pop-up notification window 708, as illustrated in FIG. 7A. When an NCC POP 142 determines that the requested web site has been blacklisted or is otherwise potentially high risk, the notification window 708 can include an image 710 or other visual indicator related to the requested web site. In some embodiments, the address bar 714 can include a textual warning that the web site is potentially high risk.

FIG. 8 is a diagram depicting illustrative browser content processing actions as a series of processing subsystems 800. In many embodiments, a browser may process sets of content (e.g., network resources such as web pages and associated embedded resources) in a series of processing actions. Illustratively, and as described above with reference to FIGS. 3-5, a remote session browsing configuration may specify a split between processing actions performed at a network computing provider (e.g., an NCC POP) and processing actions performed at a client computing device 102. This split may designate some processing actions to be performed by each of the NCC POP and client computing device 102, or may assign all processing actions to a single device or component. For example, an NCC POP may perform all of these various processing actions at the browse session instance, and send fully processed RDP processing results to the client computing device 102 for bitmap assembly and display. Any number of different remote session browsing configurations may be used by one or more browse sessions instances running at an NCC POP.

One of skill in the relevant art will appreciate that the subsystems shown here are depicted for the purpose of illustration, and are not intended to describe a necessary order or a definitive list of browser subsystems. Various browser software components may implement additional or fewer browser subsystems than are shown here, and may order the subsystems or corresponding processing actions in any number of different ways. Although the processing subsystems 800 depicted here for purposes of illustration are directed at the processing of Web pages or other Web content, one of skill in the relevant art will appreciate that the processing of other file types or network resources may be broken up in a similar manner. For example, one of skill in the relevant art will appreciate that a similar schema may be developed for the processing of images, video, audio, database information, 3d design data, or any other file format or type of data known in the art. Similar schema may also be developed for any number of device operating system or software framework processing operations, such as scheduling, memory or file management, system resource management, process or service execution or management, etc. Further, although the HTML protocol and RDP remote session communication protocols are discussed herein for the purposes of example, one of skill in the relevant art will appreciate that a remote session browsing configuration may implement any number of remote communication protocols for any number of specified processing actions, and that a remote session browsing configuration may be formulated to perform any fraction or combination of the actions identified below at any combination of the client computing device 102 and network computing provider 107.

Illustratively, the first processing subsystem involved in the processing and display of network content is the networking subsystem 802. Illustratively, the networking subsystem 802 may be responsible for all communication between the browser and content provider, including local caching of Web content. The networking subsystem is generally limited by the performance of the user's network. A remote session browsing configuration that splits processing actions at the networking subsystem 802 might include a remote session browsing configuration utilizing an HTML remote session communication protocol, where one or more caching or resource retrieval actions were performed at the NCC POP, but parsing and processing of the content was performed at the client computing device.

As network resources such as HTML documents are downloaded from the server they may be passed to an HTML subsystem 804 which parses the document, initiates additional downloads in the networking subsystem, and creates a structural representation of the document. Modern browsers may also contain related subsystems which are used for XHTML, XML and SVG documents. A remote session browsing configuration that splits processing actions at the HTML subsystem 804 might include a remote session browsing configuration utilizing an HTML remote session communication protocol, where an initial HTML page is processed at the NCC POP in order to extract embedded resource identifiers, but additional parsing and processing of the content is performed at the client computing device. In another embodiment, a remote session browsing configuration that splits processing actions at the HTML subsystem 804 might perform initial processing to create the structural representation of the HTML document, and provides a processing result including the structural representation and associated embedded resources to the client computing device for processing.

When CSS is encountered, whether inside an HTML document or an embedded CSS document, it may be passed to a CSS subsystem 806 to parse the style information and create a structural representation that can be referenced later. Illustratively, a remote session browsing configuration that splits processing actions at a CSS subsystem 806 may construct a processing result including the CSS structural representation and HTML structural representation, and provide the processing result and associated embedded resources to the client computing device for processing.

HTML documents often contain metadata, for example the information described in a document header or the attributes applied to an element. The collections subsystem 808 may be responsible for storing and accessing this metadata. A remote session browsing configuration that splits processing actions at a collections subsystem 808 may construct a processing result including processed metadata along with any other structural representations discussed above, and provide the processing result and associated embedded resources to the client computing device for processing.

When Javascript is encountered, it may be passed directly to a JavaScript subsystem 810 responsible for executing the script. The Javascript subsystem 810 has been examined fully over the years, and may be one of the most well known browser subsystems in the art. A remote session browsing configuration that splits processing actions at a Javascript subsystem 810 may construct a processing result including an internal representation of one or more Javascript scripts, including, but not limited to state data or a representation of the script in a native or intermediate form, as well as any other processed structures or data discussed above, and provide the processing result and associated embedded resources to the client computing device for processing.

Because many JavaScript engines are not directly integrated into the browser, there may be a communication layer including the marshalling subsystem 812 between the browser and the script engine. Passing information through this communication layer may generally be referred to as marshaling. A remote session browsing configuration that splits processing actions at a marshalling subsystem 812 may construct a processing result including marshalling data as well as any other processed structures, scripts, or data discussed above, and provide the processing result and associated embedded resources to the client computing device for processing.

In some embodiments, JavaScript interacts with an underlying network resource such as a Web document through the Document Object Model APIs. These APIs may be provided through a native object model subsystem 814 that knows how to access and manipulate the document and is the primary interaction point between the script engine and the browser. Illustratively, a remote session browsing configuration that splits processing actions at a native object model subsystem 814 may construct a processing result including native object model state data or API calls as well as any other processed structures, scripts, or data discussed above, and provide the processing result and any other associated embedded resources to the client computing device for processing.

Once the document is constructed, the browser may needs to apply style information before it can be displayed to the user. The formatting subsystem 816 takes the HTML document and applies styles. Illustratively, a remote session browsing configuration that splits processing actions at a formatting subsystem 816 may construct a processing result including an HTML representation with applied styles, as well as any other processed state data, API calls, structures, scripts, or data discussed above, and provide the processing result and any other associated embedded resources to the client computing device for processing.

In one embodiment, CSS is a block based layout system. After the document is styled, the next step, at a block building subsystem 818, may be to construct rectangular blocks that will be displayed to the user. This process may determine things like the size of the blocks and may be tightly integrated with the next stage, layout. A remote session browsing configuration that splits processing actions at a block building subsystem 818 may construct a processing result including block information, as well as any other processed state data, API calls, structures, scripts, or data discussed above, and provide the processing result and any other associated embedded resources to the client computing device for processing.

Subsequent to the browser styling the content and constructing the blocks, it may go through the process of laying out the content. The layout subsystem 820 is responsible for this algorithmically complex process. Illustratively, a remote session browsing configuration that splits processing actions at a layout subsystem 820 may process the various state data, API calls, structures, scripts, or data discussed above to construct a processing result including layout information for the client computing device. Illustratively, an NCC POP may make use of various data or settings associated with the client computing device or browser (e.g., as provided in the initial browse session request) in order to generate a suitable layout for the client computing device. For example, a mobile device may provide a screen resolution and a display mode to the NCC POP. The NCC POP may base layout calculations on this screen resolution and display mode in order to generate a processing result corresponding to a content representation suitable for a browser running on the mobile device. Illustratively, in various embodiments, any other subsystem implemented by the NCC POP may make use of data associated with the client computing device or browser in generating a processing result for the client.

The final stage of the process may occur inside the display subsystem 822 where the final content is displayed to the user. This process is often referred to as drawing. A remote session browsing configuration that splits processing actions at the networking subsystem 802 might include a remote session browsing configuration utilizing an RDP remote session communication protocol, where nearly all processing is performed at the NCC POP, and a processing result including bitmap data and low level interface data are passed to the client computing device for display.

FIG. 9 is a flow diagram illustrative of a new browse session routine 900 implemented by network computing provider 107 of FIG. 1. New browse session routine 900 begins at block 902. At block 904, the network computing provider 107 receives a new browse session request from client computing device 102. As previously described, the client computing device 102 may load a browser for viewing network content in response to an event or user request. Subsequent to the browser being loaded, the browser may be implemented request a new browse session. From the perspective of the user of the client computing device, the request for the new browse session corresponds to the intended request to transmit the request to one or more corresponding content providers 104. Illustratively, this request may be generated automatically as a result of the browser loading (e.g., a request for a default or “home” page), or may be generated as a result of a user following a link or entering a network address into an address bar. This browse session request may include one or more addresses or references to various network resources or other content requested by the client computing device 102. In an illustrative embodiment, the browse session request is transmitted in accordance with an API.

At block 906 the network computing provider 107 may select an associated NCC POP to instantiate a new browse session based on the browse session request. As discussed above with reference to FIG. 1, a network computing provider 107 may include any number of NCC POPs distributed across any number of physical or logical locations. A network computing provider 107 may select a NCC POP to service a browse session request based on any number of factors, including, but not limited to available NCC POP resources (e.g., available memory, processor load, network load, etc.), a financial cost of servicing the browse session request at the NCC POP, the NCC POP location respective to a client computing device 102, content provider 104, or CDN POP 116, a NCC POP cache status (e.g., whether a requested resource is already stored in an NCC POP cache), etc.

In one embodiment, the network computing provider 107 may select a number of NCC POPs to service a browse session request. For example, the network computing provider 107 may select two NCC POPs with different logical locations in the network. Each NCC POP may independently request and process network content on the behalf of the client computing device 102, and the client computing device 102 may accept data from the first NCC POP to return a processing result. Subsequent to being selected by the network computing provider 107, NCC POP 142 may obtain the browse session request. In one embodiment, NCC POP 142 may have the browse session request forwarded to it by a component of network computing provider 107. In another embodiment, NCC POP 142 or client computing device 102 may receive connection information allowing the establishment of direct communication between NCC POP 142 and client computing device 102. Illustratively, NCC POP 142 may be provided with the browse session request originally provided to network computing provider 107, may be provided with a subset of information (e.g., just a network address of requested content), or may be provided additional information not included in the original browse session request.

Subsequent to the NCC POP 142 being selected, the network computing provider 107 may cause the NCC POP 142 to instantiate a new browse session. Illustratively, instantiating a new browse session instance may include loading a new virtual machine instance and/or browser instance at the NCC POP 142, reserving or allocating device memory, storage or cache space, processor time, network bandwidth, or other computational or network resources for the new browse session. Illustratively, one or more characteristics of the new browse session instance and/or browser instance may be based on client computing device 102 information included in the browse session request. For example, the browse session request may include a device type or browser type, a device screen resolution, a browser display area, or other information defining the display preferences or capabilities of the client computing device 102 or browser. The NCC POP 142 may accordingly instantiate a virtual machine instance ancUor a browser instance with the same or similar capabilities as the client computing device 102. Illustratively, maintaining a virtual machine instance and/or browser with the same or similar capabilities as the client computing device 102 may allow the NCC POP 142 to process network content according to the appropriate dimensions and layout for display on the particular client computing device 102.

In some embodiments, the NCC POP 142 may utilize an existing virtual machine instance and/or browser instance in addition to, or as an alternative to, instating a new browse session. For example, subsequent to the NCC POP 142 being selected, the network computing provider 107 may cause the NCC POP 142 to associate an existing browser instance and/or virtual machine instance, such as one or more instances previously instantiated at the NCC POP 142, with the new browse session request. Illustratively, an existing browser session and/or virtual machine instance may correspond to another browse session, remote application session, or other remote process associated with the user or client computing device 102, or may be a previously instantiated software instance from an unrelated browse session or remote process. In other embodiments, the NCC POP 142 may instantiate a new browser or other application process in an existing virtual machine instance, or may combine the utilization of previously instantiated and newly instantiated software processes in any number of other ways. In still further embodiments, the network computing provider or NCC POP 142 may instantiate any number of new virtual machine instances and/or browser instances (or make use of existing instantiated instances) based on a single browse session request.

At block 908 the network computing provider 107 may provide a request for one or more network resources to a content provider or CDN service provider based on a network address included in the browse session request. In various embodiments, one or more network resources may be additionally or alternately retrieved from a cache local to the NCC POP 142 or otherwise associated with the network computing provider 107. One of skill in the art will appreciate that, in the case of other embodiments, the link or network address may correspond to a document or file stored in a digital file locker or other network storage location or at a cache component associated with the network computing provider 107 or client computing device 102. In some embodiments, the new session request may include a document or file in addition to or as an alternative to a network address. At block 910, the network computing provider 107 obtains the one or more network resources. Subsequent to obtaining the requested network resource, the NCC POP 142 may process the network resource to extract embedded resource identifiers.

At block 912, the network computing provider 107 may provide resource requests to one or more sources of content such as content providers, CDN service providers, and caches. The resource requests may correspond to embedded resources based on the one or more embedded resource identifiers extracted from the one or more network resource as described in block 910 above. At block 914, the network computing provider 107 may obtain these embedded resources from any number of different sources, sequentially or in parallel.

At block 916, the network computing provider 107 may process the one or more network resources and associated embedded resources to determine a remote session browsing configuration for the processing and communication of content to the client computing device 102. A remote session browsing configuration may include any proprietary or public remote protocol allowing exchange of data and user interactions or requests between a client and a remote server. The remote session browsing configuration may illustratively include both a remote session communication protocol and a processing schema for providing processed (or unprocessed) content to a client computing device for display in the content display area of a browser.

Illustratively, a remote session browsing configuration may define or specify a remote session communication protocol, including, but not limited to, a network protocol, signaling model, transport mechanism, or encapsulation format for the exchange of state data, user interactions, and other data and content between the network computing provider and the client computing device. Examples of remote session communication protocols known in the art include Remote Desktop Protocol (RDP), X-Windows protocol, Virtual Network Computing (VNC) protocol, Remote Frame Buffer protocol, HTML, etc. For example, RDP illustratively specifies a number of processing mechanisms for encoding client input (e.g., mouse movement, keyboard input, etc.) into protocol data units for provision to a remote computing device, and corresponding mechanisms for sending bitmap updates and low level interface information back to the client device. As another example, the HTML protocol illustratively provides a mechanism for providing files defining interface information and containing resources references from a server to a client, and a corresponding mechanism for a client computing device to provide requests for additional files and resources to the server. In one embodiment, the NCC POP 142 may provide an initial communication to the client computing device 102 after determining the remote session communication protocol. This initial communication may allow the client computing device 102 to prepare to receive communications in the selected remote session communication protocol, and, in the case of pull remote session communication protocols like HTTP, may cause the client computing device to send an initial resource request to the browse session instance running on the NCC POP 142.

Each remote session browsing configuration may additionally define a split of processing actions between the network computing service (e.g., NCC POP 142) and the client computing device (e.g., client computing device 102). In one embodiment, a particular split of processing actions may be based on or mandated by a particular remote session communication protocol. In another embodiment, a remote session communication protocol may allow several different splits of processing actions depending on the implementation or configuration of the protocol. For the purpose of illustration, many pieces of network content (e.g., Web pages, video, Flash documents) may require various processing actions before being displayed on a computing device. A Web page, for example, may be parsed to process various HTML layout information and references to associated resources or embedded content such as CSS style sheets and Javascript, as well as embedded content objects such as images, video, audio, etc. The HTML and each referenced object or piece of code will typically be parsed and processed before a representative object model corresponding to the Web page may be constructed. This object model may then be processed further for layout and display in a content display area of a browser at the client computing device 102. Illustrative browser processing actions are described in greater detail below with reference to FIG. 8. One of skill in the art will appreciate that, in the case of other embodiments or applications, various other processing actions may be required.

A remote session browsing configuration may specify that various of the processing actions required for display of piece of network content be performed at the remote computing device, such as the NCC POP 142, rather than at the client computing device 102. Network content partially (or wholly) processed at the network computing provider may be referred to as a processing result. As discussed below, the split of processing actions may be associated with or linked to the remote session communication protocol used for exchanging data and client input between the NCC POP 142 and client computing device 102.

For example, a remote session communication protocol such as RDP that transmits a processing result including low level interface information and bitmaps to the client computing device 142 for display may be associated with a remote session browsing configuration that specifies performing all, or nearly all, of the necessary content processing actions at the NCC POP 142. While using RDP, the NCC POP 142 may, for example, run a full instance of a browser the NCC POP 142 and transmit a processing result consisting of bitmap updates corresponding to a representation of the displayed content to the client computing device 102. The client computing device 102, in this example, may merely be required to assemble the transmitted bitmap updates for display in the content display area of the browser, and may perform none of the processing of the actual HTML, Javascript, or data objects involved in the display of an illustrative piece of network content. As another example, a remote session browsing configuration utilizing a remote session communication protocol such as HTML may transmit network content in a largely unprocessed form. The client computing device 102 may thus perform all of the processing actions required for display of network content while the NCC POP 142 performs little or no processing.

The NCC POP 142 may base its determination of a remote session browsing configuration on any number of factors, including, but not limited to, one or more characteristics of one or more of the requested resources, content provider 104, or CDN service provider 106, one or more characteristics of the content address or domain, one or more characteristics of the client computing device 102, browser or application, user, one or more characteristics of the NCC POP 142, or one or more characteristics of the network or network connection, etc. Characteristics of requested resources may include, but are not limited to, a data format, a content type, a size, processing requirements, resource latency requirements, a number or type of interactive elements, a security risk, an associated user preference, a network address, a network domain, an associated content provider, etc. Characteristics of a content provider 104, CDN service provider 106, computing device 102, or NCC POP 142 may include, but are not limited to, processing power, memory, storage, network connectivity (e.g., available bandwidth or latency), a physical or logical location, predicted stability or risk of failure, a software or hardware profile, available resources (e.g., available memory or processing, or the number of concurrently open software applications), etc. The NCC POP 142 may further consider perceived security threats or risks associated with a piece of content or domain, preferences of a client computing device or a content provider, computing or network resource costs (e.g., a financial cost of processing or bandwidth, resource usage, etc.), predetermined preferences or selection information, any additional processing overhead required by a particular remote session browsing configuration, a cache status (e.g., whether a particular resources is cached at a NCC POP 142, at the client computing device 102, or at other network storage associated with the network computing provider), a predicted delay or time required to retrieve requested network content, a preferred content provider or agreements with a content provider for a particular remote session browsing configuration or level of service, a remote session browsing configuration being used for another (or the current) browse session by the same user, or any other factor.

In some embodiments, an NCC POP 142 may base a determination of a remote session browsing configuration on past behavior or practice. For example, an NCC POP 142 that has determined a remote browse session configuration for a particular resource in the past may automatically select the same remote browse session configuration when the resource is requested by the same (or potentially a different) user. As another example, a user that has a history of frequently accessing Web sites with extensive processing requirements may automatically be assigned a remote session browsing configuration that performs the majority of processing at the NCC POP 142. In other embodiments, an NCC POP 142 may base a determination of a remote browse session configuration on predictions of future behavior. For example, an NCC POP 142 may base its determination of a remote browse session configuration for a particular resource on an analysis of past determinations made for a particular Web site, network domain, or set of related resources. A content provider that historically has provided video-heavy Web pages may be associated with a remote session browsing configuration that emphasizes video performance at the client computing device 102. Illustratively, past historical analysis and future predictions may be considered as one or more of a number of factors on which to base the remote session browsing configuration determination process, or may be definitive in the decision making process. For example, once an NCC POP 142 determines a remote session browsing configuration for a particular content provider, it may skip the remote session browsing configuration determination process for any future resources served from the content provider. Illustratively, the NCC POP 142 may re-determine a remote session browsing configuration to be associated with the content provider after a fixed period of time, or after the NCC POP 142 has identified or determined a change in the content being served by the content provider.

In other embodiments, a network resource, Web site, network domain, content provider, or other network entity may specify or otherwise request the use of a particular remote browse session configuration in a resource tag, metadata, or other communication with an NCC POP 142. The NCC POP 142 may treat the request as definitive, or may consider the request as one of multiple factors to be considered in the decision making process.

For example, a remote session browsing configuration utilizing a remote session communication protocol such as RDP may specify extensive processing to occur at the network computing provider 107 (e.g., at NCC POP 142) rather than at the client computing device 102. The remote session browsing configuration may thus leverage the processing power of the NCC POP 142 to achieve lower latencies and presentation delay when dealing with network content that requires a great deal of pre-processing (e.g., content with a great deal of CSS or Javascript information defining page layout). The NCC POP 142 may therefore select a remote session browsing configuration that performs a substantial amount of processing at the network computing provider 107 and utilizes RDP or a similar remote session communication protocol for communication of processing-intensive content. Conversely, a remote session browsing configuration that utilizes a remote session communication protocol such as HTML may specify extensive processing at the client computing device 102 rather than at the network computing provider 107. The remote session communication protocol may thus achieve smaller delays and smoother presentation when presented with simple network content that requires very little processing or network content that requires rapid change in displayed content after its initial load. For example, a Web page with embedded video may perform better performing the majority of processing locally and utilizing HTML rather than RDP as a remote session communication protocol. A remote session browsing configuration specifying extensive processing at the network computing provider 107 must process the video at the NCC POP 142 and rapidly send screen updates (e.g. by RDP) to the client computing device 102, potentially requiring a great deal of bandwidth and causing choppy playback in the browser, while a remote session browsing configuration specifying local processing may provide raw video information directly to the client computing device 102 for display (e.g. by HTML), allowing for client side caching and a smoother playback of content.

As a further example, the NCC POP 142 in communication with a client computing device 102 with extremely limited processing power may elect to use a remote session browsing configuration that requires very little processing by the client computing device, for example, using RDP to transmit NCC POP 142 processed results. Conversely, an NCC POP 142 providing an extremely interactive Web page may elect to use a remote session browsing configuration that allows the client computing device 102 to handle user interactions locally in order to preserve interface responsiveness, for example, using HTML to transmit substantially unprocessed data. As a still further example, a NCC POP 142 may base the determination of a remote session browse configuration on preferences provided by the client computing device 102. A client computing device 102 may illustratively include preferences for a remote session browse configuration in an initial browse session request, or at any other time. The NCC POP 142 may utilize these preferences as an alternative to, or in addition to any other factor or decision metric. Illustratively, allowing the client computing device 102 to set or influence the selection of a remote session browse configuration allows the NCC POP 142 to take user preferences in account when determining a remote session browse configuration. For example, a user worried about initial page load times may prefer to use a remote session browsing configuration heavy on remote processing and utilizing an RDP remote session communications protocol, while a user wishing to maintain an extremely responsive interface may prefer using a remote session browsing configuration that performs the majority of the processing on the client computing device 102, for example, using an HTML remote session communication protocol.

Illustratively, the NCC POP 142 may base a determination of a remote browsing configuration on any factor or combination of factors. For example, the NCC POP 142 may select a remote session browsing configuration based on a single factor, or may assign weights to one or more factors in making a determination. In some embodiments, the determination process of the NCC POP 142 may change based on one or more factors described above. For example, an NCC POP 142 communicating with a client computing device 102 over a network with a surplus of unused bandwidth may give a low weight to factors such as the network requirements of a remote browse session, and may give a higher weight to factors such as the latency of page interactions, while an NCC POP 142 communicating with a client computing device 102 over a limited bandwidth network may give a higher weight to factors dealing with the efficiency of the remote session browse protocol over a network.

In one embodiment, the NCC POP 142 may select a single remote session browsing configuration for a set of network content. For example, the NCC POP 142 may select a single remote session browsing configuration for a requested network resource such as a Web page. The NCC POP 142 may thus process the Web page together with all embedded content based on the selected remote browsing session protocol, and utilize the remote browsing session protocol to exchange user interaction data and updated browse session data for all embedded content associated with the Web page. In another embodiment, the NCC POP 142 may select different remote session browsing configurations for one or more resources in a set of network content. For example, a network resource such as a Web page may reference processing intensive embedded Javascript or CSS resources, as well as embedded video resources. The NCC POP 142 may select a first remote session browsing configuration for the Web page and all embedded resources excluding the embedded video resource, and a second remote session browsing configuration for the embedded video resource. Illustratively, this may result in the NCC POP 142 utilizing RDP to send a processing result to the client computing device 102 for display of the Web page and associated embedded resources, while utilizing HTTP to send the embedded video as a separate, unprocessed file. In one embodiment, the client computing device 102 may perform the minimal processing required to display the RDP processing result corresponding to the Web page and embedded resources, and may also perform additional processing necessary to display the embedded video, for example, overlaying the video on top of the displayed RDP representation of the Web page. Any number of remote session browsing configurations may be selected to correspond to any number of resources or objects included in a set of network content, regardless of whether resources or objects are obtained from a content provider 104 or CDN service provider 106 in one or more logical files or data structures.

Although the selection of a remote session browsing configuration is illustratively depicted herein as occurring after all network resources and associated embedded content have been obtained by the NCC POP 142, one skilled in the relevant art will appreciate that the selection of a remote session browsing configuration may be performed at any time. For example, the NCC POP 142 may select a remote session browsing configuration after receiving a new browse session request or related information from the client computing device, may select a remote session browsing configuration after obtaining a network resource, but before obtaining any associated embedded resources, or at any other time. In some embodiments, the NCC POP 142 may switch to a new remote session browsing configuration at some time subsequent to the client computing device 102 obtaining an initial processing result. Illustratively, the NCC POP 142 selecting a new remote session browsing configuration may occur automatically after a certain time period or event or in response to a change in network conditions, NCC POP 142 or client computing device 102 load or computing resources, or any other factor described above as potentially influencing the choice of remote session browsing configuration. Illustratively, an NCC POP 142 dealing with other types or formats of information may select a remote session protocol based on any number of similar factors. For example, one of skill in the relevant art will appreciate that a similar schema may be developed for the processing of images, video, audio, database information, 3d design data, or any other file format or type of data known in the art.

The client computing device 102 may, in various embodiments, further instantiate a parallel browsing process sequentially or simultaneously with the request for a remote browse session. In one embodiment, a client computing device 102 may instantiate a traditional local browse session as known in the art (e.g., providing content requests from the browser and processing obtained resources locally) in addition to one or more remote browse instance executing at an NCC POP 142. In another embodiment, a client computing device 102 may be provided with unprocessed network resources by the NCC POP 142. Illustratively, the network resources may have been retrieved from one or more content providers, CDNs, or cache components by the NCC POP 142. The resources may be provided to the client computing device 102 to process locally in parallel with the remote browse instance executing at the NCC POP 142. In still further embodiments, the network computing provider or NCC POP 142 may instantiate any number of new virtual machine instances and/or browser instances (or make use of existing instantiated instances) to process resources and/or send processing results to the client computing device 102 in parallel. Illustratively, the local browse session at the client computing device 102 and the remote browse session instance at the NCC POP 142 may execute in parallel.

In one embodiment, a local browse session executing at the client computing device 102 may obtain unprocessed content (e.g., html Web pages, embedded content, and other network resources) from the NCC POP 142 responsive to a browse session request. Illustratively, the content may have been retrieved by the NCC POP 142 from a content provider, CDN, or cache in response to the browse session request. The unprocessed content provided by the NCC POP 142 may include all the content associated with the browse session request or may supplement content existing in a cache of the client computing device, retrieved from a content provider or CDN, or obtained from some other source. In one embodiment, a client computing device 102 may obtain all requested content from a local cache, and may not obtain any unprocessed resources or content from the NCC POP 142. Subsequent to obtaining the unprocessed content, client computing device 102 may process the requested content in parallel with a remote browse session executing at the NCC POP 142. For example, as the local browse session executing at the client computing device 102 is processing the requested content, a remote browse session executing at the NCC POP 142 may be processing the same content at substantially the same time. Once the NCC POP 142 has performed a set of processing actions on the content to generate a processing result (e.g., as specified by a determined remote session browsing configuration), the NCC POP 142 may provide the processing result to the client computing device 102.

For the purpose of illustration, a client computing device 102 may require a longer load time to obtain and process requested network resources than a browse session instance running at the NCC POP 142. For example, the NCC POP 142 may obtain and process content quickly due to its position on the network and the relative processing power of the local client computing device as compared to the NCC POP 142. Even if the NCC POP 142 provides the client computing device 102 with all requested network content, the client computing device 102 may still obtain a processing result from NCC POP 142 before the local browse session has fully completed processing the requested resources. The client computing device 102 may complete any further processing steps and display the obtained processing result before completing local processing and display of the content. Illustratively, this may allow the client computing device 102 to take advantage of an NCC POP 142's quicker content load time relative to a traditional local browse session. Prior to the local browse session completing the processing all requested resources, the browser may process any user interactions locally and/or remotely as described in FIGS. 5 and 11 below.

Once the local browse session has fully obtained and processed resources corresponding to the requested content, the computing device 102 may determine whether to continue to display results obtained from the NCC POP 142 (and process user interactions at the NCC POP 142) using the determined remote session browsing configuration or switch to processing user interactions locally. Switching to process user interactions locally may include replacing a displayed representation of the requested resources based on a processing result obtained from the NCC POP 142 with a local display of the requested resources. For example, a browser may display a representation of a Web page corresponding to a processing result from the NCC POP 142 (e.g., RDP display information representing the rendered page) until the browser is finished processing and rendering the Web page locally. The browser may then replace the representation from the NCC POP 142 with the locally rendered representation of the Web page. Illustratively, replacing one representation with another representation may be transparent to the user. For example, the local and NCC POP 142 representations of the Web page may be identical or substantially identical. In one embodiment, when the NCC POP 142 representation of the web page is displayed, the browser may send various user interactions with the displayed page to the NCC POP 142 for processing. When the locally rendered version of the Web page is displayed, user interactions may be processed locally at the browser. Illustratively, the determination of which representation of the requested resources to display (e.g., local or from the NCC POP 142) may be based on any of the same factors described with reference to determining a remote session browse protocol in above.

In one embodiment, the client computing device 102 may switch to processing user interactions locally as soon as local resources are fully loaded. Illustratively, the remote browse session instance running at the NCC POP 142 may be terminated after switching to local processing, or the remote browse session instance may be maintained as a backup in case of unresponsiveness or a failure with regards to the local browse session. For example, the client computing device 102 may process user interactions locally, as well as sending remote user interaction data to the NCC POP 142 in accordance with the selected remote session browsing configuration. The remote user interaction data may be used by the NCC POP 142 to keep the remote browse session instance fully in parallel with the local browse process being executed by the browser at the client computing device 102. As long as the local browse session continues to handle user interactions, the NCC POP 142 may either refrain from sending updated processing results, or may send updated processing results ignored by the client computing device 102. If a problem develops with the local browse session at the client computing device 102, updated processing results may be provided to the client computing device 102 from the NCC POP 142 for processing and display in lieu of the local browse session. Illustratively, this switch from the local browse session to remote processing may be transparent to the user. In some embodiments, the client computing device 102 may switch from a local browse session to a remote browse session instance based on factors other than unresponsiveness or failure at the local browser. For example, the client computing device 102 or network computing component 107 may select between a remote and local browse session based on any of the factors enumerated with regards to determining a remote session browse protocol above

In another embodiment, the client computing device 102 may continue to process and display updated processing results from the NCC POP 142 even after the local browse session has fully loaded the requested content. The client computing device 102 may terminate the local browse session or may run the local browse session in parallel as a backup process in the converse of the example provided above. It should be appreciated that although the local browse session is described here for the purpose of illustration as being slower to load than the remote browse session instance, in some embodiments the local browse session may load the content faster than the remote browsing session, in which case the browser may process user interactions locally until the remote browse process has fully loaded the requested content. In some embodiments, the client computing device 102 may display and process user interactions through whichever browse session, local or remote, loads the requested content first.

In various other embodiments, the network computing provider 107 may instantiate multiple remote browse session instances to run in parallel in addition to or as an alternative to instantiating a local browse session. Illustratively, these parallel browse session instances may utilize any of the same or different remote session browse protocols, and may act as backups in the manner described above with regard to a local browse session, or may be used and switched between as alternatives in order to maximize browser performance at the client computing device 102. For example, in response to one or more browse session requests, the network computing provider 107 may instantiate a browse session instance running on a first NCC POP and utilizing an RDP protocol as well as browse session instance running on a second NCC POP utilizing an X-Windows protocol. The client computing device 102 or the network computing provider 107 may determine which browse session instance and protocol should be used based on performance or resource usage considerations as described with regards to determining a remote session browse protocol above.

With continued reference to FIG. 9, at block 918, the network computing provider 107 may process the obtained content, including the one or more requested network resources and embedded network resources, according to the determined remote session browsing configuration to generate an initial processing result. At block 920, the network computing provider 107 may provide the initial processing result to the client for further processing and display in the content display area of the browser. For the purposes of further example, an illustrative client new browse session interaction routine 1000 implemented by client computing device 102 is described below with reference to FIG. 10. At block 922, the start new browse session routine 900 ends.

FIG. 10 is a flow diagram illustrative of a client new browse session interaction routine 1000 implemented by client computing device 102. New browse session interaction routine 1000 begins at block 1002 in response to an event or user request causing the client computing device 102 to load a browser for viewing network content. At block 1004, the client computing device loads locally managed components of the browser, including all local interface components. As described above with reference to FIGS. 5 and 7, local interface components may include toolbars, menus, buttons, or other user interface controls managed and controlled by the software browser application or any other process executing or implemented locally at the client computing device. At block 1006, the client computing device 102 provides a request for a new browse session instance to the network computing provider 107. From the perspective of the user of the client computing device, the request for the new browse session corresponds to the intended request to transmit the request to one or more corresponding content providers 104. In other embodiment, the new session request may correspond to a request to load a file or other document (e.g., a request to load an image in a photo-editing application, etc.). Illustratively, the request may be generated automatically as a result of the browser loading (e.g., a request for a default or “home” page), or may be generated as a result of a user following a link or entering a network address into an address bar. As illustrated with respect to FIG. 2, the browse session request is transmitted first to a network computing provider 107. In an illustrative embodiment, the network computing provider 107 utilizes a registration API to accept browse session requests from the client computing device 102.

A browse session request may include any number of pieces of data or information including, but not limited to, information associated with a user, information associated with the client computing device 102 or software on the client computing device (e.g., hardware or software information, a device physical or logical location, etc.), information associated with the network 108, user or browser preferences (e.g., a requested remote session browse protocol, a preference list, a decision tree, or other information), information associated with the network computing provider 107, information associated with one or more pieces of requested network content (e.g., the network address of a network resource), etc. For example, a browse session request from the client computing device 102 may include information identifying a particular client computing device hardware specification or a hardware performance level, latency and bandwidth data associated with recent content requests, a desired security level for processing different types of content, a predetermined preference list of remote session browse protocols, and one or more network addresses corresponding to requested network resources, among others. In another example, the browse session request can include information identifying a client computing device 102 screen resolution, aspect ratio, or browser display area in the browse session request may allow the network computing provider 107 to customize the processing of network content for display on the client computing device. As previously described, the browse session request can include network address information corresponding to a requested network resource, which may be in any form including, but not limited to, an Internet Protocol (“IP”) address, a URL, a Media Access Control (“MAC”) address, etc. In one embodiment, the request for a new browse session instance may correspond to the network computing provider receiving a request for a new browse session instance at block 904 of FIG. 9 above.

At block 1008, the client computing device 102 obtains an initial processing result from the network computing provider 107. Illustratively, the format and data included in the initial processing result may vary based on the remote session browsing configuration selected by the network computing provider 107. In one embodiment, the initial processing result may include or be preceded by data informing the client computing device 102 of the choice of remote session browsing configuration and/or establishing a connection over the remote session communication protocol corresponding to the selected remote session browsing configuration. As discussed above with reference to FIGS. 8 and 9, the obtained initial processing result may include requested content with one or more processing actions performed by the network computing provider 107. Subsequent to obtaining the initial processing result, the client computing device 102 may perform any remaining processing actions on the initial processing result at block 1010.

At block 1012, the client computing device 102 displays the content corresponding to the processed initial processing result. For example, the client computing device 102 may display the processed client in the content display area 702 of a browser 700 as described in FIG. 7A above. In one embodiment, the processing result may only include display data corresponding to content displayed by a browser, and may not include display data corresponding to, for example, the interface controls of a browser instance at the NCC POP 142, the desktop of a virtual machine instance corresponding to the browse session, or any other user interface of the NCC POP 142. For example, the NCC POP 142 may process a Web page and associated content for display via RDP in a browser instance running in a virtual machine instance at the NCC POP 142. The browser instance may have one or more interface elements such as toolbars, menus, scroll bars, etc., in addition to the displayed Web page. The NCC POP 142 may send an RDP processing result corresponding to the displayed Web page only, without any of the interface elements associated with the browser. Illustratively, including an RDP processing result corresponding to the displayed Web page only may allow the browser at the client computing instance 102 to display the Web page by assembling the RDP processing result in the content display area of the browser without any further processing. In another embodiment, the RDP processing result may include a full virtual machine desktop and browser window corresponding to the full interface displayed at the NCC POP 142 browse session instance. The client computing device may automatically identify the area of the RDP processing result corresponding to the requested content, and may display only this area in the content display area of the browser.

At block 1014, the client computing device 102 processes local and remote user interactions. An illustrative routine for processing user interactions is provided below with reference to FIG. 11. At block 1016 the routine ends. Illustratively, a browse session instance instantiated by the network computing content provider 107 may terminate when a browser window or content display area is closed, may terminate when a remote session browse protocol is replaced by a parallel process at the client computing device 102, or may terminate in accordance with a timer or other event. Illustratively, if a browse session has terminated automatically due to a time-out but has associated content still displayed in a browser at the client computing device 102, later attempts by the user to interact with the content may result in a new browse session request being provided to the network computing service provider 107 to start a new browse session according to the last state of the terminated session. Illustratively, terminating a remote browse session after a time-out may allow the network computing storage provider 107 to save computing resources at the NCC POP. In one embodiment, this process may be transparent to the user at client computing device 102, even though the remote browse session has been terminated during the intervening period.

FIG. 11 is a flow diagram illustrative of a process user interaction routine 1100 implemented by a client computing device 102. Process user interaction routine 1100 begins at block 1102 in response to an interaction by a user. Illustratively, process user interaction routine 1100 may begin subsequent to the display of content in a content display area of a browser interface. For example, process user interaction routine 1100 may correspond to block 1014 of FIG. 10 above.

Illustratively, the displayed content may have one or more interactive elements, such as forms, buttons, animations, etc. User interaction with these interactive elements may require processing and display of updated content in the content display area. For example, selecting an element in a drop-down menu on a Web page may require processing and may change the configuration or visual appearance of the Web page or embedded resources. Illustratively, the processing required by user interaction with the displayed content may be handled as a local user interaction at the client computing device 102 or as a remote user interaction at the NCC POP 142 depending on the remote session browsing configuration in use. For example, if a remote session browsing configuration utilizing substantial local processing (e.g., sending unprocessed files over HTML), user interactions with displayed content may typically be handled as local user interactions at the client computing device 102. Illustratively, handling user interactions with displayed content as local user interactions at the client computing device 102 may allow for better responsiveness and fewer delays with simple user interactions (e.g., selection of a radio button, or typing text into a field), as interaction data corresponding to the interaction does not need to be sent to the NCC POP 142 for processing.

As a further example, if a remote session browsing configuration utilizing heavy remote processing of content (e.g., sending processed bitmap data over RDP) is being used as the remote session browsing configuration, all user interactions with displayed content may be handled as remote user interactions. For example, user input (e.g., keyboard inputs and cursor positions) may be encapsulated in RDP protocol data units and transmitted across network 108 to the NCC POP 142 for processing. Illustratively, the NCC POP 142 may apply the user interactions to the network content and transmit processing results consisting of updated bitmaps and interface data corresponding to an updated representation of the content back to the client computing device 102. Illustratively, handling user interactions with displayed content as remote user interactions at the NCC POP 142 may have a negative impact on interface responsiveness, as data is required to pass over the network and is limited by network latency; however, user interactions that require a substantial amount of processing may perform better when handled as remote user interactions, as the processing latency of the NCC POP 142 may be substantially lower than the processing latency of the client computing device 102.

In addition to a content display area for displaying network content, a browser may have one or more local interface components, such as toolbars, menus, buttons, or other user interface controls. Interactions with local interface components may be treated as local user interactions or remote user interactions depending on the processing required by the interaction and the remote session browsing configuration as further depicted in illustrative FIG. 7A. For example, some local interface components may be managed locally by browser code running on the client computing device, while other local interface components may have one or more locally managed aspects (e.g., button click feedback, scroll bar redraw, etc.), and one or more remote managed aspects treated as remote user interactions (e.g., page refresh, requesting a page at an address in an address bar, etc.)

At block 1104, the client computing device 102 obtains a user interaction from the user. This user interaction may be an interaction with local interface components as described in FIG. 7A and above, or may be an interaction with any interactive elements of the content displayed in the content display area of the browser, such as form fields, buttons, animations, etc. User interaction with these local interface components or interactive elements of displayed content may require local and/or remote processing depending on the nature of the component or element and the processing split specified by the remote session browsing configuration as described in FIG. 7A and above. At block 1106, the client computing device 102 determines the interaction processing requirements for the obtained user interaction. At decision block 1108, if the user interaction has local aspects (e.g., button click feedback, a change to a local browser state, a content element being processed at the client computing device, etc.) the routine 1102 moves to block 1110 to process the local aspect or aspects of the user interaction at the client computing device 102 and subsequently update the local interface components at block 1112. Illustratively, and as discussed above, aspects of the interaction and updating interface components and elements locally allows a browser to provide responsive user interfaces and content. Subsequent to processing local aspect(s) of the user interaction, or if the user interaction has no local elements (e.g., a user interaction with a content element displayed in the content display area when using a remote session browsing configuration processing entirely on the server side and utilizing an RDP remote session communication protocol) the routine 1102 moves to decision block 1114. If the user interaction has remote aspects that require processing, the routine 1102 moves to block 1116 and provides remote user interaction data to the network computing provider 107. Illustratively, in the case of a heavily server side remote session browsing configuration utilizing an RDP remote session communication protocol, the remote user interaction data may include input data such as a cursor position or keyboard input encapsulated in one or more RDP protocol data units. In some embodiments of remote session browsing configurations utilizing RDP or other remote session communication protocols, particular aspects of remote user interaction data such as cursor positions may be provided to the network computing provider 107 on a continuous basis, while in other embodiments of remote session browse configurations remote user interaction data may only be provided to the network computing provider 107 when associated with a user interaction that requires remote processing.

At block 1118, the client computing device 102 obtains an updated processing result from the network computing provider 107, the network computing provider 107 having processed the remote user interaction data to generate an updated representation of the content. At block 1120, the client computing device 102 performs any additional processing required on the updated processing result (based on the remote session browsing configuration) and at block 1122 displays the updated processing result in the content display area of the browser. At block 1124 the process user interaction routine 1102 ends. Illustratively, the routine may be executed again any number of times in response to further user interactions with the browser and displayed content.

FIG. 12 is a flow chart illustrating an example routine 1200 for requesting, retrieving, processing, and interacting with network resources, such as web sites, in a remote browsing mode. The description which follows focuses on the routine's 1200 applicability to web sites, but the routine 1200 may be applied to any number of network resources.

In certain circumstances, an end user of a client computing device 102 may want to view web sites under heightened level of security. For example, an end user may be accessing web sites from sources with which it has no prior relationship and may not trust. In other cases, an end user may be accessing web sites from sources which the end user may not trust based on prior experience, etc. In circumstances where the end user does not trust the source of the web site, a method of loading and browsing web sites on a remote computing device while only viewing the browsing result on the client computing device 102, with no web site code executing on the client computing device 102, can protect the client computing device 102 from potentially malicious or other high risk operations. Malicious operations can include intentional attempts to access an end user's personal information, alter files on the client computing device 102, download computer viruses or Trojan horses to the client computing device 102, etc. Other types of high risk operations can include operations included in the web site code which, although unintentional, may nevertheless do harm to a client computing device, cause system instability, loss of personal information, etc.

The routine 1200 begins at block 1202, when a network computing provider 107 receives a notification from a client computing device 102 to enter remote browsing mode. In one example, an end user is requesting web sites during an existing browse session. The end user accesses a web site with which it is not familiar, and may begin to notice suspicious activity, such as unexpected redirections, etc. The end user may no longer wish to have the web site rendered and/or executed locally on the client computing device 102, but still would like to view the web site and/or other similar web sites. In an effort to protect the client computing device 102 from potentially high risk operations during the remainder of the browse session, the end user activates a button 704, illustrated in FIG. 7A, on the user interface the client computing device's 102 browser application, and a notification is transmitted to the remote computing and storage provider 107, directly to the NCC POP 142, etc. In this example, because the user is activating remote browsing mode during an existing browse session, the notification can be sent to the browser application instance on the NCC POP 142 that the client computing device's 102 browser application is connected to.

In some embodiments, the NCC POP 142 may monitor the rendering and execution of web sites, for example by rendering and executing the web sites on an instance of the browsing application executing on the NCC POP 142 in parallel to the rendering and execution of the web sites on the browsing application of the client computing device 102. When the NCC POP 142 observes high risk operations, the NCC POP 142 can be configured to automatically enter remote browsing mode, prompt the user to enter remote browsing mode, etc. In some embodiments, high risk operations can include the web site accessing a system file, altering a system file, accessing an unexpected area of memory, allocating space in an unexpected area of memory, launching an unexpected process, causing network activity with unexpected network resources, causing unexpected disk I/O, etc.

In response to a notification from a client computing device 102 to enter remote browsing mode, or a determination by the NCC POP 142 that the web site may perform a high risk operation, the routine 1200 can then proceed to block 1204, where browser application on the client computing device 102 stops rendering and/or executing network resources. In remote browsing mode, the web sites can render and/or execute on an instance of the browsing application on the NCC POP 142, and therefore the no code will execute on the client computing device 102. The routine 1200 can then proceed to block 1206.

At block 1206, the NCC POP 142 can establish a remote desktop connection with the client computing device. The remote desktop connection can be established using any of a number of protocols for remotely viewing and interacting with programs, such as, for example, remote desktop protocol (RDP), remote frame buffer (RFB), or any other suitable protocol. In some embodiments, a static image of the rendered web site can be displayed in the browsing application on the client computing device 102. For example, when a web site is particularly high risk, or when the display of the web site is static and provides very little user interaction, or when network traffic must be kept to a minimum, etc. The routine 1200 can then proceed to block 1208.

At block 1208, the user can interact with the web site. The remote desktop connection between the client computing device 102 and the NCC POP 142 can provide a way for the user to transmit interactions with the web site to the NCC POP 142 for processing as if the interaction was initiated directly in the browser application instance executing on the NCC POP 142. For example, the client computing device 102 can transmit mouse clicks and keyboard input to the NCC POP 142 for processing. As a result of the interactions on the client computing device 102 and processing on the NCC POP 142, the display and other characteristics of the web site may be altered. The NCC POP 142 can transmit these alterations to the client computing device 102, and the client computing device 102 can update its display accordingly. In some embodiments, this exchange of interaction and display update data may results in a browsing experience on the client computing device 102 that is substantially similar to having the web site render and/or execute locally on the client computing device 102.

At decision block 1210, the NCC POP determines whether client computing device 102 has transmitted a notification to end remote browsing mode. In some embodiments, while the remote desktop connection is active, the NCC POP 142 can continuously process user interactions, as described above with respect to block 1208. The interactions can include activation of button to exit remote browsing mode. If such an interaction occurs, the NCC POP 142 can proceed to block 1212 and exit remote browsing mode. If there is no such interaction, the routine 1200 can continuously return to block 1208 to process any additional user interface interactions that may occur.

In one embodiment, the routine 1200 executes until a notification to exit remote browsing mode is received or a timeout occurs. For example, a user may initiate remote browsing mode, as described above, and then leave the client computing device 102 unattended for a period of time. For security or other reasons, the NCC POP 142 can be configured with a timeout, and after a period of time without any user interaction, the remote browsing session can terminate. Such a timeout can also free up resources when remote browsing sessions are no longer needed.

In some embodiments, the NCC POP 142 can be configured to monitor processing of the network resource while the client computing device 102 is accessing the resource in remote browsing mode. If the NCC POP 142 determines that the resource is not likely to perform a malicious or otherwise high risk operation on the client computing device 102, the NCC POP 142 can notify the client computing device 102. For example, the NCC POP 142 can cause display of an interactive notification on the client computing device 102, giving the user of the client computing device 102 the option to exit remote browsing mode. The notification can also be passive, for example a change in the color of the browsing application on the client computing device 102, the addition of text or an icon to the title bar of the browsing application on the client computing device 102, etc.

FIG. 13 is a flow diagram illustrating another example routine 1300 for protecting a client computing device from accessing network resources which can perform high risk operations. The description below focuses on web sites, but can also be applied to any type of network resource. The routine 1300 provides a method of monitoring the requests received from a client computing device 102 and comparing them to a blacklist, e.g.: a list of sites known to perform high risk operations. In some embodiments, the blacklist can be compiled from one or more lists maintained by third parties. In some embodiments, while executing the web site in an instance of the browsing application on the NCC POP 142, if the NCC POP 142 determines that the web site is performing a high risk operation, the web site can be added to the blacklist. In some embodiments, the users of the client computing devices 102 can define blacklists. In some embodiments, the blacklist can also include instructions regarding how a particular blacklisted site is to be handled. For example, each time an email provider is accessed, the browse session is to enter remote browsing mode in order to avoid common email-related high risk operations.

In some embodiments, access to the blacklist, in whole or in part, can be provided to other network computing providers, content providers, and other interested parties. For example, the NCC POP 142 or another component of the network computing provider can compile a blacklist from other sources and from experience with processing network resources requested by client computing devices 102. The compiled blacklist can be provided to interested parties as a web service, e.g., providing access via an API.

The routine 1300 begins execution at block 1302, when the NCC POP 142 receives a browsing request from a client computing device 102. The browsing request can include a network address of a web site, image, video, or other document, etc. The routine can then proceed to decision block 1304.

At block 1304, the NCC POP 142 can determine whether the requested network resource has been blacklisted. The NCC POP 142 can be configured to consult a shared list of web sites which have a heightened probability of performing a high risk operation. In some embodiments, the NCC POP 142 can consult a user-specific blacklist instead of, or in addition to, the shared blacklist. If the web site is blacklisted, e.g., the web site is on the list, execution of the routine 1300 can proceed to block 1308, describe below. If the web site has not been blacklisted, e.g., the web site is not on the list, execution of the routine 1300 can proceed to block 1306, where the NCC POP retrieves the resource and then proceeds to block 1316, described below.

At block 1308, the NCC POP 142 can retrieve the resource from a content source, such as a content provider 104, CDN service 106, etc. The NCC POP 142 can transmit the request to the content provider 104, and receive a response from the content source. The response can include the requested resource, embedded resources, and other data. After retrieval of the resource, execution of the routine 1300 can proceed to block 1310.

At block 1310, the NCC POP 142 can process the resource. For example, the NCC POP 142 can render and execute the resource in an instance of a browsing application, in order to determine whether the resource performs a high risk operation, capture an image of the rendered web site, establish a remote desktop connection for interacting with the web site, etc. The routine 1300 can then proceed to block 1312.

At block 1312, the NCC POP can transmit a warning to the client computing device 102. In some embodiments, the web site is not retrieved and processed before transmitting the warning to the client computing device 102. Rather, a warning can be transmitted immediately after the NCC POP 142 determines that the requested site is blacklisted. The warning can include an option for the end user of the client computing device 102 to override the warning and receive the requested web site for rendering and execution locally. In some embodiments, the warning can include an option for the end user to enter remote browsing mode to interact with the web site, as described above with respect to FIG. 12. If the NCC POP 142 determines in block 1310 that the web site performs a high risk operation, a description of the high risk operation can be included in the warning. In some embodiments, the NCC POP 142 can display a bitmap, JPEG, or other image of the rendered web site to the user of the client computing device 102 to aid the user in determining whether or not to override the warning. In some embodiments, the warning may be passive, rather than interactive. For example, the title bar, outside edge, or some other visible portion of the browser window can flash or change color or texture to indicate that the requested resource is potentially high risk, without requiring the user to override the warning to receive the resource. In some embodiments, the warning, whether passive or interactive, can be an audible warning instead of, or in addition to, being a visual warning. For example, a beep or buzz can sound, indicating that the requested resource is potentially high risk. In some cases, a passive warning may be used to inform the user that the browsing session is now entering remote browsing mode, as determined by the NCC POP 142. Execution of the routine 1300 can then proceed to decision block 1314.

At decision block 1314, the NCC POP 142 can determine whether the user of the client computing device 102 has overridden the warning, if an interactive warning was presented in block 1312. For example, the client computing device 102 can transmit a notification to the NCC POP 142 indicating whether or not the end user of the client computing device 102 has overridden the warning. If the end user has overridden the warning, execution of the routine 1300 can proceed to block 1316, where the NCC POP 142 transmits the requested web site to the client computing device 102. In some embodiments, the NCC POP 142 can provide a remote desktop connection to the instance of the browser application rendering the web site on the NCC POP 142, and in such a case the client computing device 102 will not receive the actual web site, but rather a view of the instance of the browser application executing on the NCC POP 142.

If the NCC POP 142 does not receive an override notification from the client computing device in decision block 1314, then execution of the routine 1300 can proceed to block 1318. At block 1318, the NCC POP 142 can discard the resource.

In some embodiments, the NCC POP 142 can be configured to track responses to its warnings transmitted in block 1312. The NCC POP 142 can use this data to adjust the intrusiveness of its warnings. For example, if the NCC POP 142 detects a pattern regarding a particular blacklisted web site, wherein a majority of users override the warning and receive the web site, the actual warning displayed to the user can be less intrusive or suppressed altogether, and the web site transmitted to the client computing device 102. In some embodiments, the NCC POP 142 can be configured to store a particular user's response to a warning, so that if the user requests the same web site at a later time, the web site is transmitted to the client computing device 102 without requiring an override.

FIG. 14 is a flow diagram illustrating an example routine 1400 for monitoring the execution of web sites to determine whether they present a heightened probably of performing a high risk operation. In some cases, a user of a client computing device 102 may not know beforehand that a web site may perform high risk operations, and therefore the user may not activate the remote browsing mode or add the web site to the blacklist before requesting the web site. In embodiments with a shared blacklist, the web site may not have been added to the shared blacklist yet. Even after requesting and receiving the web site, the end user may not notice that the web site is performing high risk operations. In these cases, an NCC POP 142 configured to monitor the behavior of the web site can detect high risk operations and notify the user or enter remote browsing mode without requiring any user interaction.

The routine 1400 begins at block 1402, with the start of a new browse session by a client computing device 102. As described above, the start of a new browse session request can include instantiation of a browser application on the NCC POP 142 in order to split the processing of web sites between the NCC POP 142 and client computing device 102. The routine 1400 can then proceed to block 1404.

At block 1404, the NCC POP 142 can monitor the connection with the client computing device 102 for new web site requests. As described above, the routine 1400 can incorporate a timeout feature. If the NCC POP 142 waits for a request at block 1404 for a period of time exceeding a threshold, the routine 1400 can terminate automatically.

At block 1406, the NCC POP 142 can receive from a client computing device 102 a request for a web site. When the NCC POP 142 receives a request, execution of the routine 1400 can proceed to block 1308.

At block 1408, the NCC POP 142 can retrieve the requested web site and process it. The NCC POP 142 can transmit a request for the web site to the content provider 104 hosting the web site, and receive a response from the content provider 104 including the requested web site. In some embodiments, the NCC POP 142 can retrieve the web site from any number of locations, such as a local cache, a shared cache within the network computing provider 107, a CDN service provider 106, etc. In response to receiving the requested web site, the NCC POP 142 can process the web site, including retrieving any embedded resources required to render and execute the web site, and subsequently rendering and executing the site in the instance of the browser application on the NCC POP 142. In some embodiments, the instance of the browsing application on the NCC POP 142 can render and execute the web site concurrently with the browsing application on the client computing device 102. The NCC POP 142 can be configured to perform this concurrent processing in order to determine whether high risk operations are being performed, are about to be performed, or have a probability of being performed that exceeds an acceptable threshold, as described below with respect to decision block 1410. For example, the NCC POP 142 can execute the same Javascript instructions that are executing on the client computing device 102 in order to monitor the effect that each instruction has on the overall state of the browsing application in real time. The routine 1400 can then proceed to decision block 1410.

At decision block 1410, the NCC POP 142 can determine whether the web site is performing high risk operations or has a probability of performing high risk operations that exceeds an acceptable threshold. As described above, high risk operations can include the web site accessing a system file, altering a system file, accessing an unexpected area of memory, allocating space in an unexpected area of memory, launching an unexpected process, causing network activity with unexpected network resources, causing unexpected disk I/O, etc. The NCC POP 142 is not limited to looking for specific high risk operations. For example, the network computing provider 107 can have access to a large number of requests, responses, and historical observations regarding the properties exhibited during the normal execution of web sites and during execution of malicious and other high risk web sites. In some embodiments, the network computing provider 107 can build this history over the course of thousands and potentially millions of browse sessions. The network computing provider 107, or a component thereof, can analyze this history to determine signatures of malicious or otherwise high risk behavior. In some embodiments, signatures of malicious and otherwise high risk behavior can be predetermined by a system administrator and defined within the network computing provider 107. The NCC POP 142 can use the signatures in making a determination regarding whether a specific web site executing at a specific time has a higher probability of performing malicious or otherwise high risk operations.

If the NCC POP 142 determines that the web site is performing a high risk operation or has a probability of performing a high risk operation that exceeds an acceptable threshold, the routine 1400 can proceed to block 1412. Otherwise, the routine can proceed to block 1416, where the NCC POP 142 responds to the request from the client computing device 102 by transmitting the web site, or a portion thereof, to the client computing device 102.

At block 1412, the NCC POP 142 can transmit a warning to the client computing device 102. The implementation of the warning mechanism can be similar to that described above with respect to FIG. 13. For example, the warning may be interactive, requiring a user to override the warning, or the warning may be passive, and present a visual indication to the user that the resource is potentially high risk without requiring an affirmative user override. However, in the context of the current routine 1400, the NCC POP 142 may have more information about the web site because it has rendered and executed the web site in an instance of the browsing application on the NCC POP 142. Therefore, the NCC POP 142 can provide information to the client computing device 102 about high risk operations the web site may perform in the browser application executing on the client computing device 102. For example, the NCC POP 142 can transmit a static image of the web site to the client computing device 102 so that the end user of the client computing device 102 can determine whether the web site is the one that the user expected when initially making the request, etc. After the routine 1400 transmits the warning to the client computing device 102, execution can proceed to decision block 1414 when the NCC POP 142 receives a response to the warning.

At decision block 1414, the NCC POP 142 can determine whether the user of the client computing device 102 has overridden the warning presented in block 1412. For example, the client computing device 102 can transmit a notification to the NCC POP 142 indicating whether or not the end user of the client computing device 102 has overridden the warning. If the end user has overridden the warning, execution of the routine 1400 can proceed to block 1416, where the NCC POP 142 transmits the requested web site, or a portion thereof, to the client computing device 102. Execution of the routine 1400 can then return to block 1404, where the NCC POP 142 monitors the browse session for new requests.

If the NCC POP 142 does not receive an override notification from the client computing device in decision block 1414, execution of the routine 1400 can proceed to block 1418. At block 1418, the NCC POP 142 can discard the resource. Execution of the routine 1400 can then return to block 1404, where the NCC POP 142 monitors the browse session for new requests.

While illustrative embodiments have been disclosed and discussed, one skilled in the relevant art will appreciate that additional or alternative embodiments may be implemented within the spirit and scope of the present invention. For example, the techniques described herein may be utilized, without departing from the scope of the present invention, to allow remote processing management in any number of other software applications and processes, including, but not limited to, image or video editing software, database software, office productivity software, 3d design software, audio and sound processing applications, etc. Additionally, although many embodiments have been indicated as illustrative, one skilled in the relevant art will appreciate that the illustrative embodiments do not need to be combined or implemented together. As such, some illustrative embodiments do not need to be utilized or implemented in accordance with scope of variations to the present disclosure.

Depending on the embodiment, certain acts, events, or functions of any of the algorithms or program routines described herein can be performed in a different sequence, can be added, merged, or left out all together (e.g., not all described acts or events are necessary for the practice of the routine). Moreover, in certain embodiments, acts or events can be performed concurrently, e.g., through multi-threaded processing, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially.

Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment.

Any process descriptions, elements, or blocks in the flow diagrams described herein and/or depicted in the attached FIGURES should be understood as potentially representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps in the process. Alternate implementations are included within the scope of the embodiments described herein in which elements or functions may be deleted, executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those skilled in the art. It will further be appreciated that the data and/or components described above may be stored on a computer-readable medium and loaded into memory of the computing device using a drive mechanism associated with a computer readable storing the computer executable components such as a CD-ROM, DVD-ROM, or network interface further, the component and/or data can be included in a single device or distributed in any manner. Accordingly, general purpose computing devices may be configured to implement the processes, algorithms, and methodology of the present disclosure with the processing and/or execution of the various data and/or components described above.

It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. 

What is claimed is:
 1. A system comprising: computer memory storing executable instructions; and one or more computer processors in communication with the computer memory, the one or more computer processors programmed by the executable instructions to at least: host a server-side browser application in communication with a separate client-side browser application of a client computing device; receive, by the server-side browser application, a request for a web page from the client computing device; retrieve, by the server-side browser application, at least a portion of the web page on behalf of the client computing device from a content provider; process, by the server-side browser application, the portion of the web page to detect a signature of an operation characterized as a high risk operation; determine, by the server-side browser application, based at least partly on detecting the signature of the characterized high risk operation, that processing the requested web page at the client computing device will cause performance of the characterized high risk operation on the client computing device; and in response, provide, by the server-side browser application, a view of a server-side rendered web page to the client computing device, wherein the client-side browser application is configured to display the view of the server-side rendered web page without additional rendering.
 2. The system of claim 1, wherein the one or more computer processors are further programmed by the executable instructions to at least establish a connection with the client computing device via a remote desktop protocol, wherein the view of the server-side rendered web page is provided to the client computing device via the connection.
 3. The system of claim 1, wherein the characterized high risk operation includes an operation corresponding to at least one of accessing a system file, altering a system file, accessing an unexpected area of memory, allocating space in an unexpected area of memory, launching an unexpected process, causing network activity with unexpected network resources, or causing unexpected disk I/O.
 4. The system of claim 1, wherein the one or more computer processors are programmed by the executable instructions to detect the signature of the characterized high risk operation by observing, by the server-side browser application, during the processing of at least the portion of the web page, performance of an operation identified as a high risk operation.
 5. A computer-implemented method comprising: under control of a server system comprising one or more computing devices configured to execute specific instructions, receiving a request for a network resource from a client computing device; retrieving at least a portion of the network resource from a content provider; processing the retrieved portion of the network resource to detect a signature of an operation characterized as a high risk operation; determining, based at least partly on detecting the signature of the characterized operation, that processing content associated with the requested network resource will cause performance of the characterized operation on the client computing device; and in response, transmitting a notification regarding detection of the signature of the characterized operation to the client computing device.
 6. The computer-implemented method of claim 5, wherein the notification indicates that the client computing device is either not to begin processing the network resource or is to terminate processing of the network resource.
 7. The computer-implemented method of claim 5, wherein the notification includes an instruction to cease display of network resources in a local browsing mode and to begin display of network resources in a remote browsing mode, wherein the local browsing mode comprises rendering network resources on the client computing device, and wherein the remote browsing mode comprises displaying views of network resources rendered at the server system.
 8. The computer-implemented method of claim 5, wherein the notification includes an image of the network resource.
 9. The computer-implemented method of claim 5 further comprising executing a server-side browser application in communication with a separate client-side browser application executing on the client computing device.
 10. The computer-implemented method of claim 9 further comprising: establishing a connection with the client computing device using a remote desktop protocol; and providing, to the client computing device via the connection, a view of the network resource rendered using the server-side browser application, wherein the client-side browser application is configured to display the view of the network resource rendered in the server-side browser application.
 11. The computer-implemented method of claim 9, wherein detecting the signature of the characterized operation comprises observing, during the processing of at least the portion of the network resource using the server-side browser application, performance of the characterized operation.
 12. The computer-implemented method of claim 5, wherein the characterized operation comprises an operation including at least one of accessing a system file, altering a system file, accessing an unexpected area of memory, allocating space in an unexpected area of memory, launching an unexpected process, causing network activity with unexpected network resources, or causing unexpected disk I/O.
 13. Non-transitory computer storage storing an executable network computing component that, when executed by one or more computing devices, causes the one or more computing devices to perform a process comprising: receiving a request for a network resource, the request received from a client computing device executing a client-side browser application; retrieving at least a portion of the network resource from a content provider, the portion of the network resource corresponding to the client computing device request; processing the portion of the network resource to detect a signature of an operation characterized as a high risk operation; determining, based at least partly on detecting the signature of the characterized operation, that processing content associated with the requested network resource will cause performance of the characterized operation on the client computing device; and in response, transmitting a notification regarding detection of the signature of the characterized operation to the client computing device.
 14. The non-transitory computer storage of claim 13, wherein the notification indicates that the client computing device is either not to begin processing the network resource or is to terminate processing of the network resource.
 15. The non-transitory computer storage of claim 13, wherein the notification includes an instruction to cease display of network resources in a local browsing mode and to begin display of network resources in a remote browsing mode, wherein the local browsing mode comprises rendering network resources on the client computing device, and wherein the remote browsing mode comprises displaying views of network resources rendered at the server system.
 16. The non-transitory computer storage of claim 13, wherein the notification includes an image of the network resource.
 17. The non-transitory computer storage of claim 13, the process further comprising executing a server-side browser application in communication with a separate client-side browser application executing on the client computing device.
 18. The non-transitory computer storage of claim 17, the process further comprising: establishing a connection with the client computing device using a remote desktop protocol; and providing, to the client computing device via the connection, a view of the network resource rendered using the server-side browser application, wherein the client-side browser application is configured to display the view of the network resource rendered in the server-side browser application.
 19. The non-transitory computer storage of claim 17, wherein detecting the signature of the characterized operation comprises observing, during the processing of the portion of the network resource using the server-side browser application, performance of the characterized operation.
 20. The non-transitory computer storage of claim 13, wherein the characterized operation comprises an operation including at least one of accessing a system file, altering a system file, accessing an unexpected area of memory, allocating space in an unexpected area of memory, launching an unexpected process, causing network activity with unexpected network resources, or causing unexpected disk I/O. 